Illinois River at LaGrange Lock and Dam
Critical Stages
21' - Action
23' - Flood
27' - Moderate
29' - Major
Latest Observation
Updated: 4:00 AM CST 12/16/25
Status: No Flooding
Stage: 7.42 ft
Flow: 8.09 kcfs
Forecast
| Time | Stage (ft) | Flow (kcfs) |
|---|---|---|
| 6 AM 12/16 | 7.2 | 6.3 |
| 12 PM 12/16 | 7.2 | 6.3 |
| 6 PM 12/16 | 7.2 | 6.3 |
| 12 AM 12/17 | 7.2 | 6.3 |
| 6 AM 12/17 | 7.2 | 6.3 |
| 12 PM 12/17 | 7.2 | 6.3 |
| 6 PM 12/17 | 7.2 | 6.3 |
| 12 AM 12/18 | 7.2 | 6.3 |
| 6 AM 12/18 | 7.2 | 6.3 |
| 12 PM 12/18 | 7.2 | 6.3 |
| 6 PM 12/18 | 7.2 | 6.3 |
| 12 AM 12/19 | 7.3 | 7.07 |
| 6 AM 12/19 | 7.3 | 7.07 |
| 12 PM 12/19 | 7.3 | 7.07 |
| 6 PM 12/19 | 7.3 | 7.07 |
| 12 AM 12/20 | 7.3 | 7.07 |
| 6 AM 12/20 | 7.3 | 7.07 |
| 12 PM 12/20 | 7.4 | 7.91 |
| 6 PM 12/20 | 7.4 | 7.91 |
| 12 AM 12/21 | 7.4 | 7.91 |
| 6 AM 12/21 | 7.4 | 7.91 |
| 12 PM 12/21 | 7.4 | 7.91 |
| 6 PM 12/21 | 7.4 | 7.91 |
| 12 AM 12/22 | 7.4 | 7.91 |
| 6 AM 12/22 | 7.4 | 7.91 |
| Time | Stage (ft) | Flow (kcfs) |
|---|---|---|
| 4:00 AM 12/16 | 7.42 | 8.09 |
| 3:30 AM 12/16 | 7.32 | 7.23 |
| 3:00 AM 12/16 | 7.24 | 6.6 |
| 2:30 AM 12/16 | 7.24 | 6.6 |
| 2:00 AM 12/16 | 7.3 | 7.07 |
| 1:30 AM 12/16 | 7.24 | 6.6 |
| 1:00 AM 12/16 | 7.26 | 6.75 |
| 12:30 AM 12/16 | 7.34 | 7.39 |
| 12:00 AM 12/16 | 7.3 | 7.07 |
| 11:30 PM 12/15 | 7.37 | 7.65 |
| 11:00 PM 12/15 | 7.37 | 7.65 |
| 10:30 PM 12/15 | 7.38 | 7.73 |
| 10:00 PM 12/15 | 7.37 | 7.65 |
| 9:30 PM 12/15 | 7.34 | 7.39 |
| 9:00 PM 12/15 | 7.39 | 7.82 |
| 8:30 PM 12/15 | 7.43 | 8.18 |
| 8:00 PM 12/15 | 7.33 | 7.31 |
| 7:30 PM 12/15 | 7.35 | 7.48 |
| 7:00 PM 12/15 | 7.34 | 7.39 |
| 6:30 PM 12/15 | 7.34 | 7.39 |
| 6:00 PM 12/15 | 7.34 | 7.39 |
| 5:30 PM 12/15 | 7.37 | 7.65 |
| 5:00 PM 12/15 | 7.99 | 9.38 |
| 4:30 PM 12/15 | 7.38 | 7.73 |
| 4:00 PM 12/15 | 7.41 | 8 |
| 3:30 PM 12/15 | 7.42 | 8.09 |
| 3:00 PM 12/15 | 7.47 | 8.55 |
| 2:30 PM 12/15 | 7.48 | 8.65 |
| 2:00 PM 12/15 | 7.42 | 8.09 |
| 1:30 PM 12/15 | 7.43 | 8.18 |
36' -
Lockmasters house and the lower Corps building at the lock and dam begin flooding.
35.5' -
LaGrange Road (County Highway 12) is flooded south of LaGrange Lock and Dam.
29.5' -
La Grange Lock Road (County Road 1730N) is flooded just north of the Lock and Dam.
28.8' -
County Road 500N south of La Grange is closed due to flooding.
24' -
Extensive wetland acreage south of La Grange begins flooding.
23' -
Adjacent farmland and wetlands begins flooding. Island Road across the river in western Cass County begins flooding.
20.5' -
The lock wall is completely overtopped.
16.5' -
The earthen part of the dam is overtopped.
15.5' -
Normal pool level (429.0 NGVD29).
14' -
Dam goes up at this pool level (427.5 NGVD29).
5.6' -
At and below this height, barge traffic will need to consider lowering tonnage to avoid grounding.
| Date | Stage (ft) |
|---|---|
| Jul 2, 2015 | 34.66 |
| Apr 27, 2013 | 34.5 |
| Jun 1, 1995 | 34.02 |
| Jun 4, 2019 | 33.89 |
| May 20, 2002 | 33.34 |
| Apr 19, 1979 | 32.8 |
| Apr 29, 1973 | 32 |
| Jul 29, 1993 | 32 |
| May 22, 2009 | 32 |
| May 27, 2020 | 31.35 |
| Jun 6, 2013 | 31.15 |
| Jun 29, 2010 | 30.42 |
| Apr 23, 1993 | 30 |
| May 8, 2017 | 29.75 |
| Mar 19, 2009 | 29.72 |
| Jan 20, 2005 | 29.44 |
| Sep 24, 2008 | 29.35 |
| Jun 28, 2011 | 27.86 |
| Nov 6, 2009 | 27.65 |
| May 4, 2011 | 27.47 |
Data provided by the National Weather Service.
